1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_POWERPC_BOOK3S_32_PGTABLE_H
3 #define _ASM_POWERPC_BOOK3S_32_PGTABLE_H
4
5 #include <asm-generic/pgtable-nopmd.h>
6
7 /*
8 * The "classic" 32-bit implementation of the PowerPC MMU uses a hash
9 * table containing PTEs, together with a set of 16 segment registers,
10 * to define the virtual to physical address mapping.
11 *
12 * We use the hash table as an extended TLB, i.e. a cache of currently
13 * active mappings. We maintain a two-level page table tree, much
14 * like that used by the i386, for the sake of the Linux memory
15 * management code. Low-level assembler code in hash_low_32.S
16 * (procedure hash_page) is responsible for extracting ptes from the
17 * tree and putting them into the hash table when necessary, and
18 * updating the accessed and modified bits in the page table tree.
19 */
20
21 #define _PAGE_PRESENT 0x001 /* software: pte contains a translation */
22 #define _PAGE_HASHPTE 0x002 /* hash_page has made an HPTE for this pte */
23 #define _PAGE_USER 0x004 /* usermode access allowed */
24 #define _PAGE_GUARDED 0x008 /* G: prohibit speculative access */
25 #define _PAGE_COHERENT 0x010 /* M: enforce memory coherence (SMP systems) */
26 #define _PAGE_NO_CACHE 0x020 /* I: cache inhibit */
27 #define _PAGE_WRITETHRU 0x040 /* W: cache write-through */
28 #define _PAGE_DIRTY 0x080 /* C: page changed */
29 #define _PAGE_ACCESSED 0x100 /* R: page referenced */
30 #define _PAGE_EXEC 0x200 /* software: exec allowed */
31 #define _PAGE_RW 0x400 /* software: user write access allowed */
32 #define _PAGE_SPECIAL 0x800 /* software: Special page */
33
34 #ifdef CONFIG_PTE_64BIT
35 /* We never clear the high word of the pte */
36 #define _PTE_NONE_MASK (0xffffffff00000000ULL | _PAGE_HASHPTE)
37 #else
38 #define _PTE_NONE_MASK _PAGE_HASHPTE
39 #endif
40
41 #define _PMD_PRESENT 0
42 #define _PMD_PRESENT_MASK (PAGE_MASK)
43 #define _PMD_BAD (~PAGE_MASK)
44
45 /* We borrow the _PAGE_USER bit to store the exclusive marker in swap PTEs. */
46 #define _PAGE_SWP_EXCLUSIVE _PAGE_USER
47
48 /* And here we include common definitions */
49
50 #define _PAGE_KERNEL_RO 0
51 #define _PAGE_KERNEL_ROX (_PAGE_EXEC)
52 #define _PAGE_KERNEL_RW (_PAGE_DIRTY | _PAGE_RW)
53 #define _PAGE_KERNEL_RWX (_PAGE_DIRTY | _PAGE_RW | _PAGE_EXEC)
54
55 #define _PAGE_HPTEFLAGS _PAGE_HASHPTE
56
57 #ifndef __ASSEMBLY__
58
pte_user(pte_t pte)59 static inline bool pte_user(pte_t pte)
60 {
61 return pte_val(pte) & _PAGE_USER;
62 }
63 #endif /* __ASSEMBLY__ */
64
65 /*
66 * Location of the PFN in the PTE. Most 32-bit platforms use the same
67 * as _PAGE_SHIFT here (ie, naturally aligned).
68 * Platform who don't just pre-define the value so we don't override it here.
69 */
70 #define PTE_RPN_SHIFT (PAGE_SHIFT)
71
72 /*
73 * The mask covered by the RPN must be a ULL on 32-bit platforms with
74 * 64-bit PTEs.
75 */
76 #ifdef CONFIG_PTE_64BIT
77 #define PTE_RPN_MASK (~((1ULL << PTE_RPN_SHIFT) - 1))
78 #define MAX_POSSIBLE_PHYSMEM_BITS 36
79 #else
80 #define PTE_RPN_MASK (~((1UL << PTE_RPN_SHIFT) - 1))
81 #define MAX_POSSIBLE_PHYSMEM_BITS 32
82 #endif
83
84 /*
85 * _PAGE_CHG_MASK masks of bits that are to be preserved across
86 * pgprot changes.
87 */
88 #define _PAGE_CHG_MASK (PTE_RPN_MASK | _PAGE_HASHPTE | _PAGE_DIRTY | \
89 _PAGE_ACCESSED | _PAGE_SPECIAL)
90
91 /*
92 * We define 2 sets of base prot bits, one for basic pages (ie,
93 * cacheable kernel and user pages) and one for non cacheable
94 * pages. We always set _PAGE_COHERENT when SMP is enabled or
95 * the processor might need it for DMA coherency.
96 */
97 #define _PAGE_BASE_NC (_PAGE_PRESENT | _PAGE_ACCESSED)
98 #define _PAGE_BASE (_PAGE_BASE_NC | _PAGE_COHERENT)
99
100 /*
101 * Permission masks used to generate the __P and __S table.
102 *
103 * Note:__pgprot is defined in arch/powerpc/include/asm/page.h
104 *
105 * Write permissions imply read permissions for now.
106 */
107 #define PAGE_NONE __pgprot(_PAGE_BASE)
108 #define PAGE_SHARED __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW)
109 #define PAGE_SHARED_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW | _PAGE_EXEC)
110 #define PAGE_COPY __pgprot(_PAGE_BASE | _PAGE_USER)
111 #define PAGE_COPY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)
112 #define PAGE_READONLY __pgprot(_PAGE_BASE | _PAGE_USER)
113 #define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)
114
115 /* Permission masks used for kernel mappings */
116 #define PAGE_KERNEL __pgprot(_PAGE_BASE | _PAGE_KERNEL_RW)
117 #define PAGE_KERNEL_NC __pgprot(_PAGE_BASE_NC | _PAGE_KERNEL_RW | _PAGE_NO_CACHE)
118 #define PAGE_KERNEL_NCG __pgprot(_PAGE_BASE_NC | _PAGE_KERNEL_RW | _PAGE_NO_CACHE | _PAGE_GUARDED)
119 #define PAGE_KERNEL_X __pgprot(_PAGE_BASE | _PAGE_KERNEL_RWX)
120 #define PAGE_KERNEL_RO __pgprot(_PAGE_BASE | _PAGE_KERNEL_RO)
121 #define PAGE_KERNEL_ROX __pgprot(_PAGE_BASE | _PAGE_KERNEL_ROX)
122
123 #define PTE_INDEX_SIZE PTE_SHIFT
124 #define PMD_INDEX_SIZE 0
125 #define PUD_INDEX_SIZE 0
126 #define PGD_INDEX_SIZE (32 - PGDIR_SHIFT)
127
128 #define PMD_CACHE_INDEX PMD_INDEX_SIZE
129 #define PUD_CACHE_INDEX PUD_INDEX_SIZE
130
131 #ifndef __ASSEMBLY__
132 #define PTE_TABLE_SIZE (sizeof(pte_t) << PTE_INDEX_SIZE)
133 #define PMD_TABLE_SIZE 0
134 #define PUD_TABLE_SIZE 0
135 #define PGD_TABLE_SIZE (sizeof(pgd_t) << PGD_INDEX_SIZE)
136
137 /* Bits to mask out from a PMD to get to the PTE page */
138 #define PMD_MASKED_BITS (PTE_TABLE_SIZE - 1)
139 #endif /* __ASSEMBLY__ */
140
141 #define PTRS_PER_PTE (1 << PTE_INDEX_SIZE)
142 #define PTRS_PER_PGD (1 << PGD_INDEX_SIZE)
143
144 /*
145 * The normal case is that PTEs are 32-bits and we have a 1-page
146 * 1024-entry pgdir pointing to 1-page 1024-entry PTE pages. -- paulus
147 *
148 * For any >32-bit physical address platform, we can use the following
149 * two level page table layout where the pgdir is 8KB and the MS 13 bits
150 * are an index to the second level table. The combined pgdir/pmd first
151 * level has 2048 entries and the second level has 512 64-bit PTE entries.
152 * -Matt
153 */
154 /* PGDIR_SHIFT determines what a top-level page table entry can map */
155 #define PGDIR_SHIFT (PAGE_SHIFT + PTE_INDEX_SIZE)
156 #define PGDIR_SIZE (1UL << PGDIR_SHIFT)
157 #define PGDIR_MASK (~(PGDIR_SIZE-1))
158
159 #define USER_PTRS_PER_PGD (TASK_SIZE / PGDIR_SIZE)
160
161 #ifndef __ASSEMBLY__
162
163 int map_kernel_page(unsigned long va, phys_addr_t pa, pgprot_t prot);
164 void unmap_kernel_page(unsigned long va);
165
166 #endif /* !__ASSEMBLY__ */
167
168 /*
169 * This is the bottom of the PKMAP area with HIGHMEM or an arbitrary
170 * value (for now) on others, from where we can start layout kernel
171 * virtual space that goes below PKMAP and FIXMAP
172 */
173 #include <asm/fixmap.h>
174
175 /*
176 * ioremap_bot starts at that address. Early ioremaps move down from there,
177 * until mem_init() at which point this becomes the top of the vmalloc
178 * and ioremap space
179 */
180 #ifdef CONFIG_HIGHMEM
181 #define IOREMAP_TOP PKMAP_BASE
182 #else
183 #define IOREMAP_TOP FIXADDR_START
184 #endif
185
186 /* PPC32 shares vmalloc area with ioremap */
187 #define IOREMAP_START VMALLOC_START
188 #define IOREMAP_END VMALLOC_END
189
190 /*
191 * Just any arbitrary offset to the start of the vmalloc VM area: the
192 * current 16MB value just means that there will be a 64MB "hole" after the
193 * physical memory until the kernel virtual memory starts. That means that
194 * any out-of-bounds memory accesses will hopefully be caught.
195 * The vmalloc() routines leaves a hole of 4kB between each vmalloced
196 * area for the same reason. ;)
197 *
198 * We no longer map larger than phys RAM with the BATs so we don't have
199 * to worry about the VMALLOC_OFFSET causing problems. We do have to worry
200 * about clashes between our early calls to ioremap() that start growing down
201 * from ioremap_base being run into the VM area allocations (growing upwards
202 * from VMALLOC_START). For this reason we have ioremap_bot to check when
203 * we actually run into our mappings setup in the early boot with the VM
204 * system. This really does become a problem for machines with good amounts
205 * of RAM. -- Cort
206 */
207 #define VMALLOC_OFFSET (0x1000000) /* 16M */
208
209 #define VMALLOC_START ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
210
211 #ifdef CONFIG_KASAN_VMALLOC
212 #define VMALLOC_END ALIGN_DOWN(ioremap_bot, PAGE_SIZE << KASAN_SHADOW_SCALE_SHIFT)
213 #else
214 #define VMALLOC_END ioremap_bot
215 #endif
216
217 #define MODULES_END ALIGN_DOWN(PAGE_OFFSET, SZ_256M)
218 #define MODULES_VADDR (MODULES_END - SZ_256M)
219
220 #ifndef __ASSEMBLY__
221 #include <linux/sched.h>
222 #include <linux/threads.h>
223
224 /* Bits to mask out from a PGD to get to the PUD page */
225 #define PGD_MASKED_BITS 0
226
227 #define pte_ERROR(e) \
228 pr_err("%s:%d: bad pte %llx.\n", __FILE__, __LINE__, \
229 (unsigned long long)pte_val(e))
230 #define pgd_ERROR(e) \
231 pr_err("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
232 /*
233 * Bits in a linux-style PTE. These match the bits in the
234 * (hardware-defined) PowerPC PTE as closely as possible.
235 */
236
237 #define pte_clear(mm, addr, ptep) \
238 do { pte_update(mm, addr, ptep, ~_PAGE_HASHPTE, 0, 0); } while (0)
239
240 #define pmd_none(pmd) (!pmd_val(pmd))
241 #define pmd_bad(pmd) (pmd_val(pmd) & _PMD_BAD)
242 #define pmd_present(pmd) (pmd_val(pmd) & _PMD_PRESENT_MASK)
pmd_clear(pmd_t * pmdp)243 static inline void pmd_clear(pmd_t *pmdp)
244 {
245 *pmdp = __pmd(0);
246 }
247
248
249 /*
250 * When flushing the tlb entry for a page, we also need to flush the hash
251 * table entry. flush_hash_pages is assembler (for speed) in hashtable.S.
252 */
253 extern int flush_hash_pages(unsigned context, unsigned long va,
254 unsigned long pmdval, int count);
255
256 /* Add an HPTE to the hash table */
257 extern void add_hash_page(unsigned context, unsigned long va,
258 unsigned long pmdval);
259
260 /* Flush an entry from the TLB/hash table */
flush_hash_entry(struct mm_struct * mm,pte_t * ptep,unsigned long addr)261 static inline void flush_hash_entry(struct mm_struct *mm, pte_t *ptep, unsigned long addr)
262 {
263 if (mmu_has_feature(MMU_FTR_HPTE_TABLE)) {
264 unsigned long ptephys = __pa(ptep) & PAGE_MASK;
265
266 flush_hash_pages(mm->context.id, addr, ptephys, 1);
267 }
268 }
269
270 /*
271 * PTE updates. This function is called whenever an existing
272 * valid PTE is updated. This does -not- include set_pte_at()
273 * which nowadays only sets a new PTE.
274 *
275 * Depending on the type of MMU, we may need to use atomic updates
276 * and the PTE may be either 32 or 64 bit wide. In the later case,
277 * when using atomic updates, only the low part of the PTE is
278 * accessed atomically.
279 */
pte_update(struct mm_struct * mm,unsigned long addr,pte_t * p,unsigned long clr,unsigned long set,int huge)280 static inline pte_basic_t pte_update(struct mm_struct *mm, unsigned long addr, pte_t *p,
281 unsigned long clr, unsigned long set, int huge)
282 {
283 pte_basic_t old;
284
285 if (mmu_has_feature(MMU_FTR_HPTE_TABLE)) {
286 unsigned long tmp;
287
288 asm volatile(
289 #ifndef CONFIG_PTE_64BIT
290 "1: lwarx %0, 0, %3\n"
291 " andc %1, %0, %4\n"
292 #else
293 "1: lwarx %L0, 0, %3\n"
294 " lwz %0, -4(%3)\n"
295 " andc %1, %L0, %4\n"
296 #endif
297 " or %1, %1, %5\n"
298 " stwcx. %1, 0, %3\n"
299 " bne- 1b"
300 : "=&r" (old), "=&r" (tmp), "=m" (*p)
301 #ifndef CONFIG_PTE_64BIT
302 : "r" (p),
303 #else
304 : "b" ((unsigned long)(p) + 4),
305 #endif
306 "r" (clr), "r" (set), "m" (*p)
307 : "cc" );
308 } else {
309 old = pte_val(*p);
310
311 *p = __pte((old & ~(pte_basic_t)clr) | set);
312 }
313
314 return old;
315 }
316
317 /*
318 * 2.6 calls this without flushing the TLB entry; this is wrong
319 * for our hash-based implementation, we fix that up here.
320 */
321 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
__ptep_test_and_clear_young(struct mm_struct * mm,unsigned long addr,pte_t * ptep)322 static inline int __ptep_test_and_clear_young(struct mm_struct *mm,
323 unsigned long addr, pte_t *ptep)
324 {
325 unsigned long old;
326 old = pte_update(mm, addr, ptep, _PAGE_ACCESSED, 0, 0);
327 if (old & _PAGE_HASHPTE)
328 flush_hash_entry(mm, ptep, addr);
329
330 return (old & _PAGE_ACCESSED) != 0;
331 }
332 #define ptep_test_and_clear_young(__vma, __addr, __ptep) \
333 __ptep_test_and_clear_young((__vma)->vm_mm, __addr, __ptep)
334
335 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
ptep_get_and_clear(struct mm_struct * mm,unsigned long addr,pte_t * ptep)336 static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
337 pte_t *ptep)
338 {
339 return __pte(pte_update(mm, addr, ptep, ~_PAGE_HASHPTE, 0, 0));
340 }
341
342 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
ptep_set_wrprotect(struct mm_struct * mm,unsigned long addr,pte_t * ptep)343 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr,
344 pte_t *ptep)
345 {
346 pte_update(mm, addr, ptep, _PAGE_RW, 0, 0);
347 }
348
__ptep_set_access_flags(struct vm_area_struct * vma,pte_t * ptep,pte_t entry,unsigned long address,int psize)349 static inline void __ptep_set_access_flags(struct vm_area_struct *vma,
350 pte_t *ptep, pte_t entry,
351 unsigned long address,
352 int psize)
353 {
354 unsigned long set = pte_val(entry) &
355 (_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC);
356
357 pte_update(vma->vm_mm, address, ptep, 0, set, 0);
358
359 flush_tlb_page(vma, address);
360 }
361
362 #define __HAVE_ARCH_PTE_SAME
363 #define pte_same(A,B) (((pte_val(A) ^ pte_val(B)) & ~_PAGE_HASHPTE) == 0)
364
365 #define pmd_pfn(pmd) (pmd_val(pmd) >> PAGE_SHIFT)
366 #define pmd_page(pmd) pfn_to_page(pmd_pfn(pmd))
367
368 /*
369 * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
370 * are !pte_none() && !pte_present().
371 *
372 * Format of swap PTEs (32bit PTEs):
373 *
374 * 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
375 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
376 * <----------------- offset --------------------> < type -> E H P
377 *
378 * E is the exclusive marker that is not stored in swap entries.
379 * _PAGE_PRESENT (P) and __PAGE_HASHPTE (H) must be 0.
380 *
381 * For 64bit PTEs, the offset is extended by 32bit.
382 */
383 #define __swp_type(entry) ((entry).val & 0x1f)
384 #define __swp_offset(entry) ((entry).val >> 5)
385 #define __swp_entry(type, offset) ((swp_entry_t) { ((type) & 0x1f) | ((offset) << 5) })
386 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) >> 3 })
387 #define __swp_entry_to_pte(x) ((pte_t) { (x).val << 3 })
388
pte_swp_exclusive(pte_t pte)389 static inline int pte_swp_exclusive(pte_t pte)
390 {
391 return pte_val(pte) & _PAGE_SWP_EXCLUSIVE;
392 }
393
pte_swp_mkexclusive(pte_t pte)394 static inline pte_t pte_swp_mkexclusive(pte_t pte)
395 {
396 return __pte(pte_val(pte) | _PAGE_SWP_EXCLUSIVE);
397 }
398
pte_swp_clear_exclusive(pte_t pte)399 static inline pte_t pte_swp_clear_exclusive(pte_t pte)
400 {
401 return __pte(pte_val(pte) & ~_PAGE_SWP_EXCLUSIVE);
402 }
403
404 /* Generic accessors to PTE bits */
pte_write(pte_t pte)405 static inline int pte_write(pte_t pte) { return !!(pte_val(pte) & _PAGE_RW);}
pte_read(pte_t pte)406 static inline int pte_read(pte_t pte) { return 1; }
pte_dirty(pte_t pte)407 static inline int pte_dirty(pte_t pte) { return !!(pte_val(pte) & _PAGE_DIRTY); }
pte_young(pte_t pte)408 static inline int pte_young(pte_t pte) { return !!(pte_val(pte) & _PAGE_ACCESSED); }
pte_special(pte_t pte)409 static inline int pte_special(pte_t pte) { return !!(pte_val(pte) & _PAGE_SPECIAL); }
pte_none(pte_t pte)410 static inline int pte_none(pte_t pte) { return (pte_val(pte) & ~_PTE_NONE_MASK) == 0; }
pte_exec(pte_t pte)411 static inline bool pte_exec(pte_t pte) { return pte_val(pte) & _PAGE_EXEC; }
412
pte_present(pte_t pte)413 static inline int pte_present(pte_t pte)
414 {
415 return pte_val(pte) & _PAGE_PRESENT;
416 }
417
pte_hw_valid(pte_t pte)418 static inline bool pte_hw_valid(pte_t pte)
419 {
420 return pte_val(pte) & _PAGE_PRESENT;
421 }
422
pte_hashpte(pte_t pte)423 static inline bool pte_hashpte(pte_t pte)
424 {
425 return !!(pte_val(pte) & _PAGE_HASHPTE);
426 }
427
pte_ci(pte_t pte)428 static inline bool pte_ci(pte_t pte)
429 {
430 return !!(pte_val(pte) & _PAGE_NO_CACHE);
431 }
432
433 /*
434 * We only find page table entry in the last level
435 * Hence no need for other accessors
436 */
437 #define pte_access_permitted pte_access_permitted
pte_access_permitted(pte_t pte,bool write)438 static inline bool pte_access_permitted(pte_t pte, bool write)
439 {
440 /*
441 * A read-only access is controlled by _PAGE_USER bit.
442 * We have _PAGE_READ set for WRITE and EXECUTE
443 */
444 if (!pte_present(pte) || !pte_user(pte) || !pte_read(pte))
445 return false;
446
447 if (write && !pte_write(pte))
448 return false;
449
450 return true;
451 }
452
453 /* Conversion functions: convert a page and protection to a page entry,
454 * and a page entry and page directory to the page they refer to.
455 *
456 * Even if PTEs can be unsigned long long, a PFN is always an unsigned
457 * long for now.
458 */
pfn_pte(unsigned long pfn,pgprot_t pgprot)459 static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
460 {
461 return __pte(((pte_basic_t)(pfn) << PTE_RPN_SHIFT) |
462 pgprot_val(pgprot));
463 }
464
465 /* Generic modifiers for PTE bits */
pte_wrprotect(pte_t pte)466 static inline pte_t pte_wrprotect(pte_t pte)
467 {
468 return __pte(pte_val(pte) & ~_PAGE_RW);
469 }
470
pte_exprotect(pte_t pte)471 static inline pte_t pte_exprotect(pte_t pte)
472 {
473 return __pte(pte_val(pte) & ~_PAGE_EXEC);
474 }
475
pte_mkclean(pte_t pte)476 static inline pte_t pte_mkclean(pte_t pte)
477 {
478 return __pte(pte_val(pte) & ~_PAGE_DIRTY);
479 }
480
pte_mkold(pte_t pte)481 static inline pte_t pte_mkold(pte_t pte)
482 {
483 return __pte(pte_val(pte) & ~_PAGE_ACCESSED);
484 }
485
pte_mkexec(pte_t pte)486 static inline pte_t pte_mkexec(pte_t pte)
487 {
488 return __pte(pte_val(pte) | _PAGE_EXEC);
489 }
490
pte_mkpte(pte_t pte)491 static inline pte_t pte_mkpte(pte_t pte)
492 {
493 return pte;
494 }
495
pte_mkwrite_novma(pte_t pte)496 static inline pte_t pte_mkwrite_novma(pte_t pte)
497 {
498 return __pte(pte_val(pte) | _PAGE_RW);
499 }
500
pte_mkdirty(pte_t pte)501 static inline pte_t pte_mkdirty(pte_t pte)
502 {
503 return __pte(pte_val(pte) | _PAGE_DIRTY);
504 }
505
pte_mkyoung(pte_t pte)506 static inline pte_t pte_mkyoung(pte_t pte)
507 {
508 return __pte(pte_val(pte) | _PAGE_ACCESSED);
509 }
510
pte_mkspecial(pte_t pte)511 static inline pte_t pte_mkspecial(pte_t pte)
512 {
513 return __pte(pte_val(pte) | _PAGE_SPECIAL);
514 }
515
pte_mkhuge(pte_t pte)516 static inline pte_t pte_mkhuge(pte_t pte)
517 {
518 return pte;
519 }
520
pte_mkprivileged(pte_t pte)521 static inline pte_t pte_mkprivileged(pte_t pte)
522 {
523 return __pte(pte_val(pte) & ~_PAGE_USER);
524 }
525
pte_mkuser(pte_t pte)526 static inline pte_t pte_mkuser(pte_t pte)
527 {
528 return __pte(pte_val(pte) | _PAGE_USER);
529 }
530
pte_modify(pte_t pte,pgprot_t newprot)531 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
532 {
533 return __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot));
534 }
535
536
537
538 /* This low level function performs the actual PTE insertion
539 * Setting the PTE depends on the MMU type and other factors.
540 *
541 * First case is 32-bit in UP mode with 32-bit PTEs, we need to preserve
542 * the _PAGE_HASHPTE bit since we may not have invalidated the previous
543 * translation in the hash yet (done in a subsequent flush_tlb_xxx())
544 * and see we need to keep track that this PTE needs invalidating.
545 *
546 * Second case is 32-bit with 64-bit PTE. In this case, we
547 * can just store as long as we do the two halves in the right order
548 * with a barrier in between. This is possible because we take care,
549 * in the hash code, to pre-invalidate if the PTE was already hashed,
550 * which synchronizes us with any concurrent invalidation.
551 * In the percpu case, we fallback to the simple update preserving
552 * the hash bits (ie, same as the non-SMP case).
553 *
554 * Third case is 32-bit in SMP mode with 32-bit PTEs. We use the
555 * helper pte_update() which does an atomic update. We need to do that
556 * because a concurrent invalidation can clear _PAGE_HASHPTE. If it's a
557 * per-CPU PTE such as a kmap_atomic, we also do a simple update preserving
558 * the hash bits instead.
559 */
__set_pte_at(struct mm_struct * mm,unsigned long addr,pte_t * ptep,pte_t pte,int percpu)560 static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
561 pte_t *ptep, pte_t pte, int percpu)
562 {
563 if ((!IS_ENABLED(CONFIG_SMP) && !IS_ENABLED(CONFIG_PTE_64BIT)) || percpu) {
564 *ptep = __pte((pte_val(*ptep) & _PAGE_HASHPTE) |
565 (pte_val(pte) & ~_PAGE_HASHPTE));
566 } else if (IS_ENABLED(CONFIG_PTE_64BIT)) {
567 if (pte_val(*ptep) & _PAGE_HASHPTE)
568 flush_hash_entry(mm, ptep, addr);
569
570 asm volatile("stw%X0 %2,%0; eieio; stw%X1 %L2,%1" :
571 "=m" (*ptep), "=m" (*((unsigned char *)ptep+4)) :
572 "r" (pte) : "memory");
573 } else {
574 pte_update(mm, addr, ptep, ~_PAGE_HASHPTE, pte_val(pte), 0);
575 }
576 }
577
578 /*
579 * Macro to mark a page protection value as "uncacheable".
580 */
581
582 #define _PAGE_CACHE_CTL (_PAGE_COHERENT | _PAGE_GUARDED | _PAGE_NO_CACHE | \
583 _PAGE_WRITETHRU)
584
585 #define pgprot_noncached pgprot_noncached
pgprot_noncached(pgprot_t prot)586 static inline pgprot_t pgprot_noncached(pgprot_t prot)
587 {
588 return __pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) |
589 _PAGE_NO_CACHE | _PAGE_GUARDED);
590 }
591
592 #define pgprot_noncached_wc pgprot_noncached_wc
pgprot_noncached_wc(pgprot_t prot)593 static inline pgprot_t pgprot_noncached_wc(pgprot_t prot)
594 {
595 return __pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) |
596 _PAGE_NO_CACHE);
597 }
598
599 #define pgprot_cached pgprot_cached
pgprot_cached(pgprot_t prot)600 static inline pgprot_t pgprot_cached(pgprot_t prot)
601 {
602 return __pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) |
603 _PAGE_COHERENT);
604 }
605
606 #define pgprot_cached_wthru pgprot_cached_wthru
pgprot_cached_wthru(pgprot_t prot)607 static inline pgprot_t pgprot_cached_wthru(pgprot_t prot)
608 {
609 return __pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) |
610 _PAGE_COHERENT | _PAGE_WRITETHRU);
611 }
612
613 #define pgprot_cached_noncoherent pgprot_cached_noncoherent
pgprot_cached_noncoherent(pgprot_t prot)614 static inline pgprot_t pgprot_cached_noncoherent(pgprot_t prot)
615 {
616 return __pgprot(pgprot_val(prot) & ~_PAGE_CACHE_CTL);
617 }
618
619 #define pgprot_writecombine pgprot_writecombine
pgprot_writecombine(pgprot_t prot)620 static inline pgprot_t pgprot_writecombine(pgprot_t prot)
621 {
622 return pgprot_noncached_wc(prot);
623 }
624
625 #endif /* !__ASSEMBLY__ */
626
627 #endif /* _ASM_POWERPC_BOOK3S_32_PGTABLE_H */
628